Issue validation error when given composer name does not match
the one in latest version.
Remove composer name on import, when persisted composer name does not match
the one in uploaded version.
Simplify eID again, as we can now rely on composer_name in extension table
being correct.

A checkbox lets users confirm they uploaded the extension
to Packagist and they own the package there.
Additionally, when this box is checked the composer name
needs to be provided as double confirmation.
If this composer name is valid, registered on Packagist
and matches the composer name of the latest uploaded
extension version, the composer name is persisted.